Well Markus, it's likely that this will come someday, probably when flarum will become a trustworthy successor of current esotalk forum software. But I want to give you some aspects why I am doing this:
I want to keep control over my images/screenshots/zip files. Even in other forums with upload-functionality I rather use public-folder links. It's a kill-switch If you need a name for this. It's my data and I want to keep control. And if I decide not to share something anymore I can do this. This would be more complicated if I would need to quit membership in several forums and even then all my links, images and assets would remain active.
2) Easy updating
For updating you just overwrite the file in the public folder, boom, done. No additional announcement or editing of existing posts needed. It's a time-saver.
3) Easy uploading/ sharing
When talking about time-saving. Of course I could use ordinary FTP for uploading and HTTP sharing. But it would take additional steps to do this. I would need to start my transmit ftp-client but there are drawbacks sometimes, when working behind firewalls with blocked ftp ports or when trying to share something from my mobile devices.